An EPMA Study on KNbO 3 and NaNbO 3 Single Crystals - Potential Reference Materials for Quantitative Microanalysis (original) (raw)

Electron Microscopy Studies of Potassium Sodium Niobate Ceramics

Microscopy and Microanalysis, 2005

Using electron microscopy, K0.5Na0.5NbO3 (KNN) ceramics sintered at 1030°C for 8 h and 1100°C for 2 and 24 h was studied. The scanning electron microscopy and X-ray spectrometry revealed that the materials consisted of a matrix phase in which the (Na+K)/Nb ratio corresponded closely to the nominal composition and a small amount of Nb-rich secondary phase. A bimodal microstructure of

Analytical Studies on Aluminium Doped KNbO 3 Single Crystal

A ferroelectric KNbO 3 single crystal was grown by flux method by using K 2 CO 3 and Nb 2 O 5 as a starting materials having a molar ratio of 1:2:1, with an impurity Al 2 O 3 (100mg). X-ray powder diffraction (XRD), transmission spectrum, dielectric constant and thermal analysis measurements, were performed to characterize the KNbO 3 crystal. The XRD confirmed the phase of grown crystal as to be KNbO 3. Lattice parameters were found to be a=5. 68863, b=3. 96864, c=5. 73482. Obviously, dielectric anomaly with increasing temperature (Tc) can be observed indicating phase transition temperatures and Curie temperature, through the dielectric constant measurement and the Curie temperature of KNbO 3 crystal was found to be 435˚C.